The latest Gallup poll indicates that 14 percent of the people "moderately disapprove" of Barack Obama's performance as president and 39 percent "strongly disapprove."

Since Obama won two presidential elections, chances are that some of those who now "strongly disapprove" of what he has done voted to put him in office. We all make mistakes, but the real question is whether we learn from them.

With many people now acting as if it is time for "a woman" to become president, apparently they have learned absolutely nothing from the disastrous results of the irresponsible self-indulgence of choosing a President of the United States on the basis of demographic characteristics, instead of individual qualifications.

It would not matter to me if the next five presidents in a row were all women, if these happened to be the best individuals available at the time. But to say that we should now elect "a woman" president in 2016 is to say that we are willfully blind to the dangers of putting life and death decisions in the hands of someone chosen for symbolic reasons.

If we were to choose just "a woman" as our next president, would that mean that any criticism of that president would be considered to be a sign of being against women?

No public official should be considered to be above criticism — and the higher up that official is, the more important it is to hold his or her feet to the fire when it comes to carrying out duties involving the life and death of individuals and the fate of the nation.

We have not yet had a Jewish president. If and when we do, does that mean that any criticism of that individual should be stigmatized and dismissed as anti-Semitism? What of our first Italian American president, our first Asian American president?

Human beings of every background are imperfect creatures. When they are in a position high enough for their imperfections to bring disasters to more than 300 million Americans, the last thing we need is to stifle criticism of what they do.

It is by no means guaranteed that this country will survive the long-run consequences of the disastrous decisions already made by Barack Obama, especially his pretense of stopping Iran's becoming a nuclear power. Obama may no longer be in office when those chickens come home to roost.

If we wake up some morning and find some American city in radioactive ruins, will we connect the dots and see this as a consequence of voting to elect an unknown and untried man, for the sake of racial symbolism?

Among those who look around for someone to blame, how many will look in the mirror?

Presidents already have too much insulation from criticism — and from reality.

When President Calvin Coolidge caught everyone by surprise in 1928, by announcing that he would not run for reelection, despite a prosperous economy and his own personal popularity, he simply said, "I do not choose to run." Coolidge was a man of very few words, despite his knowledge of multiple languages. Someone once said that Coolidge could be silent in five different languages.

But, when he later wrote a small autobiography, Coolidge explained the inherent dangers in the office of President of the United States, especially when one person remains in the White House too long.

"It is difficult for men in high office to avoid the malady of self-delusion. They are always surrounded by worshippers. They are constantly, and for the most part sincerely, assured of their greatness.

"They live in an artificial atmosphere of adulation and exaltation which sooner or later impairs their judgment. They are in grave danger of becoming careless and arrogant."

Of presidents who served eight years in office, he said, "in almost every instance" the last years of their terms show little "constructive accomplishments" and those years are often "clouded with grave disappointments."

Another president chosen for demographic representation (whether by race, sex or whatever), and further insulated from criticism and from reality, is the last thing we need.

Thomas Sowell, a National Humanities Medal winner, is an American economist, social theorist, political philosopher and author. He is currently Senior Fellow at the Hoover Institution, Stanford University.